Underfloor duct system



April 2, 1935. J. M. G. FULLMAN 1,996,371

UNDERFLOOR DUCT SYSTEM Filed DSG. 4, 1931 2 Sheets-Sheet l BYW ATTORNEYS INVENTOR i April 2,1935. J.M G FULLMAN' 1,996,371

UNDERFLOOR DUCT SYSTEM Filed Dec. 4, '19s;k 2 sheets-sheet 2 22 2B HQ..

BY ATTORNEY 6 Patented Apr. 2, 1935 UNITED PATENT? oFFlcsgf A s y ,51,996,371 Y o o UNDERFLon nUc'r SYSTEM James u'llinan, sewickley, Pa., assignor to i National'Electric Products Corporation, New fv York, N. Y., a corporation ofpDelaware Application-December@ 1331, Serial o. 528,927

` I iclai'msi. (c1. A247428) This invention relates to' an improvedunderi'loork duct' system and to improved means forv providing outlets. More particularly'the present invention relates to an improvement in the lconstruction disclosed in `United States patent to Otto A. Fredrickson, No, 1,776,656," dated September 23, v1930. According'tc the' arrangement therein'set forth, forms in the 'shapeof plugs were provided which were'attached Vto ducts or conduits and after such forms were removed, the duct proper had to have av section thereof removed to provideaccess to the interior of the duct. Difiiculty is sometimes experienced inremoving the duct materialthroughv the pre-formed opening tothe floor surface and in certain 'cases' the opening in the duct must be reamed or other operations thereon performed in order that an outlet fixture may be attached thereto'. f

The present invention has for one ofi its objects the provision of an improved construction wherein, as before, removablev plug-shaped forms are provided which forms, in lieu Vof bein'glsecured over a closed duct, are secured tothe vduct vover pre-formed openings in the duct with `the duct constructed to alternatively receive the forms or outlet securing means whereby duct cutting and nishing operations are obviated.

Further and other objects of the present invention will be hereinafter set forth in the accompanying specification and claims and illustrated in the drawings which by way of illustration show what I now consider to be a preferred embodiment of my invention.

Fig. 1 is a perspective view of a section of duct or conduit with the improved plug in juxtaposition for attachment thereto;

Fig. 2 shows the improved plug secured to a duct and with concrete flooring over the duct and around the plug; i

Fig. 3 shows a View similar to Fig. 2 but with the plug removed;

Fig. 4 shows an extension fitting secured to the duct and disposed in the pre-formed hole in the concrete;

Fig. 5 is a view similar to Fig. 4 but with a slight modication in the form of extension pipe securing means;

Fig. 6 is a modied form of plug with a diaphragm provided therein for supporting concrete in position therein; andV Figs. 7 and 8 illustrate other different forms of plugs which may be used.

In more detail in the drawings, Il) in the various gures represents the duct or conduit or other underiioor vconduit through which the wires are `intended. to be passed. The 'ducts III `are provided 'at intervals'with 'the openings II and adjacent the openingsII are tapped holes I2-to receive fastening screws I3.v 'I'hese fastening screws are disposed in the .bottom of plug shaped form members I4jwhich are preferably of conical configuration and provided with closed bottoms I5. In Fig. 2.ap1ug-shaped form I4 is shown secured to the duct' I 0 withthe closed bottom portion I5 disposed over-the opening II and with they screws I3 extending into the tapped holes of the duct. Concrete I6V is poured in place around the conical plug I4. suitable closure for the top of the plug-shaped form. VSuch closure may be disposed as shown or maybe disposed flush with the top ofthe floor I6. When it is desired to provide an outlet opening at any point the plug-shaped form .I4 is removed, such removal is affected by unscrewing the screws I 3,` access to the screws being provided through the hollow interior of the plugshaped form. After the. removal of the plug-v shapedform the pre-formed opening I8 is leftv in 'the'concreteiabovethe Aduct II). Fig. 4 shows the next step wherein an extension fitting assemblage is applied to the duct. In this figure the part generally designated I9 is the adapter fitting part, this part being provided with lug portions which are suitably drilled to register I'I represents any with the tapped holes I2 of the duct and permit fastening screws I3a to be inserted so as to secure the adapter fitting I9 to the duct. The adapter fitting part I 9 is provided with a through opening preferably rounded off at the bottom as shown at 2I and tapped to receive a vertical standpipeA 22. Adjacent the licor, a floor flange 23 may be provided to cover up the top of the conical p reformed opening I8. It will be understood that part 22 constitutes the usual pipe portion of the extension fitting assemblage commonly called the standpipe.

According to the embodiment shown in Fig. 5, the adapter fitting part I9 here designated Isa, is tapped from top to bottom, the intermediate shoulder portion being omitted. In other respects the construction is similar to that shown in Fig. 4. y

Fig. 6 shows a different form of plug form Mb. This plug form has a shouldered portion 25 spaced intermediate the top and closed bottom I5, which shouldered portion 25 is adapted to receive a collapsible diaphragm 26. The collapsible diaphragm 26 is adapted to support a crete instead of lifting out of the formas is the case with the other constructions;V

With all of the various embodimentstheA plug shaped forms are provided with securing means,

extending through tapped openings in the duct and the duct is provided with pre-formed openings II. The arrangement is such that the duct is alternatively adapted to receive either a plugshaped form oran extension fitting assemblage.

What I claim is: g l 1. A duct system including a'buried conduit having a substantially dat undeformed upper Wall portion provided with spaced openings therethrough for selectively vvreceiving adapterV fitting parts or removable plugs, removable plugs with at bottom portions abutting the at top of the'duct around the spaced openings and screw fastening means extending through the flat bottoms of the plugs and engaging screw holes disposed in fiat top of the duct slightly away from the foregoing openings therein, said screw holes being also adapted to receive screw fastenings for adapter fittings uponV removal of the plugs, and adapter fittings shaped to extend into the duct openings and to also abut the top flat of the duct and to be secured' thereto by the aforesaid last mentioned screw fastening means, said screw fastening means of each plug being disposed within the lateral peripheral wall of the plug and thereby accessible for unfastening operation without removal of flooring material exteriorly adjacent said peripheral wall.

2. A conduit system ,including a conduit provided with a plurality of openings therein, each opening having adjacent to and spaced from it threaded openings in the conduit wall, said threaded openings interchangeably receiving screw means for attaching plug-shaped forms which serve as closures for the other openings and which plug-shaped forms flatly abut at their bottoms the flat top wall -of the conduit, and screw means for attaching extension fitting adapters which fit into an opening upon removal ofa plug, said conduit system including one or more of said plug-shaped forms each having the aforesaid screw means removably attaching the form over a corresponding opening in the conduit, saidV screw means being disposed within the lateral peripheral wall of the form and thereby accessible for effecting removal of the form without removal of flooring material exteriorly adjacent said peripheral wall.

3. In an underfloor conduit system, in combination, a duct having an undeforrned upper wall with an extension fitting adapter receiving opening therein, a plug for providing a preformed passage in the fioor from said adapter opening to the floor surface, fastening screw means associated with Vthe plug for removably securing the plug to' the duct in said passageproviding relation, said undeformed duct wall having small openings adjacent to and outside of the said .adapter receiving opening and said small openings including screw threads, for removably and interchangeably receiving the aforesaid fastening screw means of the plug and corresponding fastening screw means of an extension fitting adapter when the plug is removed, and said fastening screw means of the plug being disposed within the lateral peripheral wall of the plug and thereby accessible for removal of the plug, when the latter is secured to the duct.

4. The combination of claim 3 in which the plug is provided with a diaphragm disposed at a point intermediate the top and bottom of said plug.

' JAMES M. G. FULLMAN. 

